| 摘要 |
PROBLEM TO BE SOLVED: To control the steering of a power steering gear for a front two-axle vehicle even if an engine-driven pump stops. SOLUTION: This power steering gear involves a main power cylinder 6 and sub power cylinder 30 controlling the steering of the front and rear steering wheels of a front two-axle vehicle, a main pump 10 driven by a vehicle engine, a main control valve 15 for switching channels, a sub pump 11 driven by any means other than the engine, and a sub control valve 31 for switching channels. The gear also includes a cylinder switch means 40 which feeds fluid pressure from the main control valve to both power cylinders and interrupts the channel between both power cylinders when the supply of the fluid pressure from the main pump is stopped, and a pilot pressure check valve 50 between a fluid pressure supply passage 51 from the sub pump and a return passage 52, which communicates the return passage with the supply passage by the fluid pressure from the main pump as pilot pressure. |
